gecko-dev/mailnews/base/resources/content/mailNavigatorOverlay.xul

<?xml version="1.0"?>

<!-- retrieve generic commands -->
<?xul-overlay href="chrome://messenger/content/mailOverlay.xul"?>

<!DOCTYPE window SYSTEM "chrome://messenger/locale/mailNavigatorOverlay.dtd" >

<overlay id="mailNavigatorOverlay"
         xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">

  <script type="application/x-javascript">
  <![CDATA[
    function openComposeWindow(pageUrl, pageTitle, attachPage)
    {                                                                          
      var params = Components.classes["@mozilla.org/messengercompose/composeparams;1"].createInstance(Components.interfaces.nsIMsgComposeParams);
      if (params)
      {
        params.composeFields = Components.classes['@mozilla.org/messengercompose/composefields;1'].createInstance(Components.interfaces.nsIMsgCompFields);
        if (params.composeFields)
        {
          params.composeFields.body = pageUrl;
          params.composeFields.subject = pageTitle;
          if (attachPage)
          {
            var attachmentData = Components.classes["@mozilla.org/messengercompose/attachment;1"].createInstance(Components.interfaces.nsIMsgAttachment);
            if (attachmentData)
            {
              attachmentData.url = pageUrl;
              params.composeFields.addAttachment(attachmentData);
            }
          }
          params.bodyIsLink = true;

          var composeService = Components.classes["@mozilla.org/messengercompose;1"].getService(Components.interfaces.nsIMsgComposeService);
          if (composeService)
            composeService.OpenComposeWindowWithParams(null, params);
      }                                                                         
      }                                                                         
    }   
  
    function sendLink(pageUrl, pageTitle)
    {
      try {
        openComposeWindow(pageUrl, pageTitle, false);
      } catch(ex) { dump("Cannot Send Link: " + ex + "\n"); }
    }

    function sendPage(aDocument)
    {
      if (!aDocument)
        aDocument = window._content.document;
        
      var pageUrl = aDocument.URL;
      var pageTitle = aDocument.title;

      try {
        openComposeWindow(pageUrl, pageTitle, true);
      } catch(ex) { dump("Cannot Send Page: " + ex + "\n"); }
    }

    function initMailContextMenuItems(aEvent)
    {
      var shouldShowSendPage = !gContextMenu.onImage && !gContextMenu.onLink && !gContextMenu.onTextInput;
      gContextMenu.showItem("context-sendpage", shouldShowSendPage);

      var shouldShowSendLink = gContextMenu.onLink;
      gContextMenu.showItem("context-sendlink", shouldShowSendLink);
      
      gContextMenu.showItem("context-sep-apps", gContextMenu.shouldShowSeparator("context-sep-apps"));
    }
      
    var gAddedMailContextMenuPopupListener = false;
    function initMailContextMenuPopupListener(aEvent)
    {
      // This is really lame, but we can't seem to add a bubbling listener to the DOMWindow (!)
      if (gAddedMailContextMenuPopupListener)
        return;
      var popup = document.getElementById("contentAreaContextMenu");
      popup.addEventListener("popupshowing", initMailContextMenuItems, false);
      gAddedMailContextMenuPopupListener = true;
    }

    addEventListener("load", initMailContextMenuPopupListener, true);
  ]]>
  </script>         

  <!-- navigator specific commands -->
  <commandset id="tasksCommands">
    <command id="cmd_sendPage" oncommand="sendPage();"/>
    <command id="Browser:SendLink" oncommand="sendLink(window._content.location.href, window._content.document.title);"/>
  </commandset>
         
  <!-- navigator specific UI items -->
  <menupopup id="menu_NewPopup">
    <menuitem id="menu_newCard" position="3"/>
    <menuitem id="menu_newMessage" position="2"/>
  </menupopup>

  <menupopup id="menu_FilePopup">
    <menuitem id="menu_sendPage" label="&sendPage.label;" accesskey="&sendPage.accesskey;" command="cmd_sendPage" position="11"/>
    <menuitem id="menu_sendLink" label="&sendLinkCmd.label;" accesskey="&sendLinkCmd.accesskey;" command="Browser:SendLink" position="12"/>
  </menupopup>

  <popup id="contentAreaContextMenu">
    <menuitem id="context-sendpage"
              label="&sendPage.label;"
              accesskey="&sendPage.accesskey;"
              oncommand="sendPage(gContextMenu.target.ownerDocument);"
              insertafter="context-sep-save"/>
    <menuitem id="context-sendlink"
              label="&sendLinkCmd.label;"
              accesskey="&sendLinkCmd.accesskey;"
              oncommand="sendLink(gContextMenu.linkURL(), gContextMenu.linkText());"
              insertafter="context-sep-save"/>
  </popup> 
  
</overlay>